This is my first post on this issue even though I am on my fourth lens from B&H. The first one was 960 and soft. The second was 032 and had a very noticeable clicking sound. The third was 062 and had decentering problems. My fourth is 062 and my initial test showed that it was most likely a keeper. Checked the zoom right out of the box in my office with normal HVAC sounds and did not notice clicking. Shot my usual tests vis a vis my 24-105 (both indoors and outdoors) and it still looked good. Shot a number of photos over the weekend and was pleased. A couple of nights ago it was on a tripod in my home with the zoom extended. I walked over to it and zoomed it back to the 24 mm position and by chance my ear was pretty close to the side of the lens. When I zoomed it in, I could hear a very slight clicking sound, similar to the earlier version but much softer. Someone in an earlier post said it did not sound like a tumbler on a safe being turned, but I think it does sound like one but very soft. Bottom line, I can only hear it if my ear is next to the side of the lens (obviously not a good shooting position). My earlier one with clicking was very noticeable even when not close to it. If I hold the lens in my hands in front of me and zoom, I do not hear clicking. I have not tried video with it (on a 5dMkIII). If I can't hear it in normal shooting then maybe it is not a big deal. However, I am concerned about what the sound means in a few years since we tend to keep lenses a long time. Any of you have one with a similar sound and did you keep it? Did it get better or worse? I am still within the return period and even with rebates this is a very expensive lens. I have a few other L lenses and I have never had a problem like this. At this point still debating whether to keep, try for #5 or get a refund.

I was going to hold out for a potential IS version for double usage on video, but recent double dip sales combined with it be greatly useful for events made me pull the trigger.

I still have to do some more thorough sharpness tests, but this is an 042 from Amazon and definitely no clicking or squeaking after a lot of zoom testing. Sharpness appears to be good too, though I have to do more through testing. Seems like others in this thread had luck with 042 also.

Also, the zoom is not particularly tight, in fact I'd say it is a bit looser than the 24-105 I used to have was when I first got it and definitely a lot smoother.

I just picked up one and it does have a slight ticking sound when zooming in and out. My serial is a 062, ordered from B&H. It's only audible when holding close in a quite room. Not really that concerned as it's under warranty and image sharpness tests are all superb with no decentered elements. I would agree that this certainly isn't optimal on a lens of this build quality, but it's very slight and hard to say whether it's just a change in manufacturing or a minor defect. I usually send every newly purchased lens in for calibration at some point, so we'll see if Canon notes anything regarding this issue.

...Bottom line, I can only hear it if my ear is next to the side of the lens (obviously not a good shooting position). My earlier one with clicking was very noticeable even when not close to it. If I hold the lens in my hands in front of me and zoom, I do not hear clicking. I have not tried video with it (on a 5dMkIII). If I can't hear it in normal shooting then maybe it is not a big deal. However, I am concerned about what the sound means in a few years since we tend to keep lenses a long time. ....

My 24-70 f2.8 II has similar level of noise as yours. I can only hear it when stick my ear right to the barrel. My Serial is 032. However, I have way passed the return deadline so I guess I can only have Canon to check it out.

The interesting thing is that I recently purchased a 70-200 f2.8 is II with similar clicking noise when zooming. The noise, again, can only be heard when sticking my ear very close to the barrel. So now I am so confused if there are manufacture defects on both lens or it is just normal.

This sux...I just received my now and first thing I did was tested it w/my fingers crossed--NO LUCK! Mine has a ticking/clicking sound too when zooming. And I don't have to put it next to my ear to hear it (probably due to all these reports I'm reading, I'm consciously listening for it so it comes easier). My batch is 06 (6/2013) from B&H. Going back for exchange.

Does anyone with the lens experience the ticking sounds disappearing for a while then coming back? For example, you hear ticking and put the lens down for a few hours, come back, and then the ticking is gone. But then you put it down again, come back a few hours later, and the ticks are back again? It seems random and I'm not sure what causes it....I don't think it's temperature since the lens is in the same environment the whole time.

Does anyone with the lens experience the ticking sounds disappearing for a while then coming back? For example, you hear ticking and put the lens down for a few hours, come back, and then the ticking is gone. But then you put it down again, come back a few hours later, and the ticks are back again? It seems random and I'm not sure what causes it....I don't think it's temperature since the lens is in the same environment the whole time.

Don't forget, friction = heat. So when you zoom, you create friction, which warms up the gaskets perhaps making them expand... Let it sit, gaskets cool down, contract, no more click? A theory.

Does anyone with the lens experience the ticking sounds disappearing for a while then coming back? For example, you hear ticking and put the lens down for a few hours, come back, and then the ticking is gone. But then you put it down again, come back a few hours later, and the ticks are back again? It seems random and I'm not sure what causes it....I don't think it's temperature since the lens is in the same environment the whole time.

Yeah I had a 03 (March) copy and returned it to B&H. It would have the ticking sound and then it would disappear. Then after moving the zoom barrel later you would hear it again so its possible.

Has anyone made it past the "batch" of lenses with issues? I've had 4 copies with clicking noises, a lens with a bubble in the front element, two lenses with AFMA issues at 70 mm (both were amazing at 24 mm, but awful at 70 mm) and a lens that was great until wider than f/4, then the resolution plummeted. So, this is eight copies that I've tested with origination dates from Oct 2012 through June 2013.

I know that there are good copies of this lens out there. Actually, I almost kept the copy with a small bubble as it was great in every other way. As was the one copy with the clicking issue that I tested (other three I sent back as soon as I heard the clicking).

But I just want to see if anyone has recently purchased a good copy of this lens?

BTW, I've tested my other lenses and the 24-70 II is the first lens I've ever returned.

Also, for those of you that have to hold your ear up to the lens to hear the clicking....that is much softer than what I've experienced. The four that I had with the clicking it was audible enough that I instantly heard it with the lens at a normal distance (18 to 24 inches) from my ear.

I wonder what is up with this lens lately and these issues... I have a first release and never had any of these problems... Zoom ring is quiet as can be, sharp end to end and minimal MA required (-2W and +1T). Glad I was an early adopter lol (although I paid for it...)

I am really not sure. What concerns me is that people are reporting several types of issues. I've called and talked with Canon that they have stated that there are no advisories for the 24-70 II. So, at least thus far that they are acknowledging, this is normal.

That said, it isn't normal with any other canon lens or camera I've had. I've definitely upped my testing of lenses since getting this lens. Lots of practice, after all. But I've gone back and tested a couple of other lenses of mine and they test out just fine.

I just packaged up the last of the lenses I am going to test. I want the "better colors/contrast" that I've heard others talk about. But I am done. I'm going to let the sale price go and see what comes around in 4-6 months. Maybe an IS version, maybe lower prices, maybe primes, or maybe a Tamron.

I just receive my copy from B&H.... no luck... don't have to put my ear next to it and I still able to hear.

for people reading the date code. do you guys read it on the box or Warranty Card? the number on my warranty card starting with 042xxxxxxx... not sure if that is the right number I should get the date code from.